package com.itheima.reggie.contoreller;

import cn.hutool.http.server.HttpServerResponse;
import com.itheima.reggie.common.Result;

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

@RestController
@Slf4j
@RequestMapping(value = "/common")
public class CommonController {
    //拿到yml里保存的文件路径
    @Value("${takeOutFile.fileLocaltion}")
    private String basePath;

    @PostMapping("/upload")
    public Result<String> upload(MultipartFile file){
        //file 是一个临时文件，需要转存到指定位置，否则请求完成后临时文件会删除
//        log.info("file:{}",file.toString());
//        return null;

        //原始文件名
        String originalFilename = file.getOriginalFilename();
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));
        //使用UUID随机生成文件名，防止因为文件名相同造成文件覆盖
        String fileName = UUID.randomUUID().toString()+ suffix;

        //创建一个目录对象
        File dir = new File(basePath);
        //判断当前目录是否存在
        if(!dir.exists()){
            dir.mkdir();
        }

        //将临时文件转存到指定位置
        try {
            file.transferTo(new File(basePath+fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }

        return Result.success(fileName);
    }

    //文件下载
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        //输入流，通过输入流读取文件内容
        try {
            FileInputStream fileInputStream = new FileInputStream(new File(basePath + name));
            //输出流，通过输出流将文件写回浏览器，在浏览器中展示图片
            ServletOutputStream outputStream = response.getOutputStream();

            int len=0;
            byte[] bytes = new byte[1024];
            while ((len=fileInputStream.read(bytes))!=-1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }
            outputStream.close();
            fileInputStream.close();

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

}
